1. Field of the Invention
This invention relates to machines for baling solid materials into a compact bale, and more particular to baling machines having two separate rams, one for gathering and compacting the material and the other for ejecting the compacted material through a discharge outlet.
2. Description of the Prior Art
Continuous extrusion type baling machines have been well known in the baling art and have long been used for baling waste material, such as paper, cardboard, used beverage cans, solid waste and the like. These baling machines have conventionally comprised a horizontal baling chamber having a floor, having sides for constraining the bale laterally and having a discharge passage from which the bales were ejected, and a feed hopper opening in the top side of the baling chamber for delivering the material to be baled. A ram having a forward platen or head reciprocated in the baling chamber past the feed hopper opening between a rearward position of retraction and a forward position of extension and compaction. The ram head was conventionally driven by a hydraulic cylinder mechanism.
In many baling machines, two rams have been used. The first ram gathered the material falling into the chamber from the hopper and compressed the material in the baling chamber against a solid end wall. The second ram extending generally transversely to the first ram ejected the compressed material from the baling chamber. The baling chamber in dual ram baling machines comprised the solid end wall opposite the gathering ram against which the material is compacted and a discharge passage opposite the ejection ram through which the finished bale was ejected from the chamber.
In operation, a charge of compressible material was dumped into the hopper and dropped into the gathering chamber when the gathering ram was retracted. The gathering ram was reciprocated back and forth between its retracted and extended positions, and successive charges were compressed and compacted together in the baling chamber against the solid end wall by the repeated strokes of the gathering ram head. After the material was compressed to its desired density, the gathering ram head was moved to a position at which its inner face formed one of the sidewalls of the baling chamber, and the ejection ram head was advanced to eject the bale through the discharge outlet on one side of the baling machine. An automatic strapping or tying mechanism was positioned at the discharge outlet. When a bale of compressed material was ejected from the baling chamber, the bale was bound and tied with a suitable number of wires.
Examples of dual head baling machines are shown in U.S. Pat. No. 3,613,556, issued to Wright et al.; U.S. Pat. No. 3,576,161, issued to Wright; U.S. Pat. No. 4,658,719, issued to Jackson et al.; U.S. Pat. No. 4,729,301, issued to Smith et al.; U.S. Pat. No. 5,007,337, issued to Newsom; U.S. Pat. No. 5,201,266, issued to Schmalz et al.; U.S. Pat. No. 5,558,014, issued to Robinson; and U.S. Pat. No. 5,081,922, issued to Rudd et al.; the disclosures of which are all hereby incorporated by reference.
A problem develops if there is insufficient material to form a full sized bale or if it is desired to create a bale which is less than full size. The effective size of the baling chamber of prior art machines has been fixed in size, with its dimensions determined by the front face of the gathering ram head when the gathering ram is in its advanced position, the front face of the ejection ram head when the ejection ram is in its retracted position, the solid end wall, and the discharge outlet. While the end wall may be retractable to accommodate the ejection of an oversized bale, it does not allow changing the effective size of the baling chamber. If less than the desired amount of material fills this chamber when the bale is completed, the result is a bale of less than desired density, and such a bale may be unstable and have a tendency to come apart during handling.